COIL

The several coils with the same 'YName' can be mentally represented as one microchip with multiple inputs and one output.
Normal and inverted input are directly transfers the input state (normal or inverted) to the output every time in every PLC cycle.

This simple ladder diagram shows a side effect (flip-flop, jitter of the output signal). First, at the beginning of the PLC cycle, the output Y1 is reset to 0, and then the output Y1 is set to 1 and remains 1 to the end of the PLC cycle time.

When the input button is pressed, then output is inverted.

To prevent the side effect, use an additional internal relay. All modification should be produced with the internal relay R1 and only one Y1 coil output will be on the ladder diagram. R1 has jitter, but Y1 is stable.